Release clutch for grinding mills



J. S. BUCKWALTER RELEASE CLUTCH FOR GRINDING MILLS June 28, 1927.1,633,844

Filed July 1, 1924 2 Sheets-Sheet l June 28, 1927.

1,633,844 J. s. BUCKWALTER RELEASE CLUTCH FOR GRINDING MILLS Filed July1, 1924 2 Sheets-Shut 2 Patented June 28, 1927.

UNITED STATES 1,633,844 PATENT OFFICE.

JACOB S. BUCKWALTER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THEENTERPRISE MANUFACTURING COMPANY OF PENNSYLVANIA, OF PHILADELPHIA,PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

RELEASE CLUTCH FOR GRINDING MILLS.

Application filed July 1,

clogged, by foreign matter passing between the grinding plates.

In the accompanying drawings:

Fig. 1 is a sectional elevation of a grinding mill illustrating myinvention;

Fig. 2 is a sectional view on the line 22,

Fig. 1;

Fig. 3 is a detached perspective View of the shaft and the groovedcollar thereon;

Fig. 4 is a detached perspective view of the latch; and

Fig. 5 is a detached perspective view of the plunger that engages thelatch and holds it vieldingly in position.

eferring to the drawings, 1 is the body of a grinding mill having ahopper 2 and an outlet 3 for the material that has been ground. A fixedgrinding disk 4 is secured to the body in any suitable manner. Anelectric motor 5 is secured to a flange 6 of the body 1. A motor shaft 7is notched at the end to receive a similarly formed end of a mill shaft8, which is mounted in a bearing 9 in a cap plate 10 that is secured tothe body 1. Secured by a pin 11 to the shaft is a collar 12 having agroove 13, Fig. 3. The walls of this groove are inclined, as shownclearly in the drawings, to allow the latch to be released underexcessive pressure.

Mounted loosely on the shaft 8 is a feed screw 14 to which is attachedthe rotating grinding disk 15 and the carrying disk 16. These two disksare secured to the feed screw by screws17. Extending over the jointbetween the motor shaft and the mill shaft 8 is a sleeve 18 having ahead 19.- Between this head and the end of the feed screw 14 is a spring20. There is a space 21 between the end of the sleeve and the inner endof the opening in the feed screw so that the feed screw, and its disk,can be adjusted towards and from the fixed grinding disk 4. The spring20 holds the shaft 8 yieldingly against a ball thrust bearing 22.Mounted on a stud 23 on the disk 16 is a latch 24,

1924'. Serial No. 723,534.

Fig. 4, which has a projection 25 that is adapted to fitthe groove 13 inthe collar 12. This projection has beveled sides 26, whichfitthe beveledsides of the groove 13. The bevel is such that, when the grinding disk15 is clogged, the latch is forced out of the groove. This allows themotor and the mill. shaft to turn freely, independently of the grindingdisk. The latch has an we tension 27, which forms a finger hold by whichit can be forced into the groove, or manually removed from the groove. Astop 28 on'the disk 16 limits the outward movement of the latch 24.

In order to hold the latch frictionally either in or out of position, aplunger 29 is provided, which is adapted to slide in a projection 30 onthe disk 16. Back of this plunger is a spring 31, which bears against ascrew 32 in the rear of the projection. The end of the plunger isbeveled, as shown in Figs. 2 and 5, and either rests against one of thebeveled walls 26 of the projection 25 of the latch, or in the bevelednotch 33 in the latch.

When the plunger is in the notch 33, the latch is held in engagementwith the collar 12, as shown by full lines in Fig. 2. WVhen the latch israised, the plunger holds the latch out of engagement. In thepresentinstance, the cap plate 10 has an extension 34, in which ismounted a cam disk 35, carrying the ball thrust bearing 22. This camldisk is prevented from turning inthe cap plate. In the present lnstance,1t has an arm 36, whlch enters a groove in the bearing 9. The back ofthe cam plate has three cam surfaces, which correspond to three camsurfaces on a. cam block 37 that is secured to a sleeve 38, which ismounted on the extension 34 of the cap plate 10. The screws 39 securethe cam block to the sleeve. On turning the sleeve, the grinding disk 15can be adjusted towards the fixed disk 4. A pin 40 which is mounted inthe sleeve is projected yieldingly by a. spring 41 into one of a seriesof grooves 42 in the end of the cap plate. The means of adjusting themovable grinding disk forms no part of the present invention. 7

This invention is particularly adapted for grinding material, such ascoffee. Occasionally, the mill becomes clogged. The foreign matterenters the space between the disks and unless there is releasemechanism, one of the parts is liable to be broken. By providing thelatch, as soon as the pressure is in excessof the spring pressure, thelatch is forced out of the groove in the collar 12 and the collar, andits shaft, turn independently of the disk. On removing the cap plate 10,the disk can be freed of the obstructions and the latch can be reset.

I claim:

The combination in clutch release mechanism of a. shaft; a collar on theshaft having a transverse groove therein; amovable member mounted on theshaft; a latch pivoted to said member and having a projection extendinginto the groove in the collar and having a beveled wall in which is abeveled notch, and a spring-pressed plunger mounted on the movablemember and having a beveled end arranged to engage the notch in thelatch to retain the latch in engagement with the collar, or with thebeveled wall to hold the latch out of engagement with the collar.

J ACOB S. BUCKlVi-lLTEl-l.

